Improvement in the manufacture of pitch



UNITED STATES PATENT OFFICE.

A. H. EMERY, OF NEW YORK, N; Y.

I MPROVEMENT IN THE MANUFACTURE OF PITCH.

Specification forming partlof Letters Patent No. 19.24 8, dated August 8, 1867:.

To all whom it may concern Be it known that I, A. H. EMERY, of the city, county, and State of New York, have invented a new and Improved Process of Manufacturing Pitch from Pine Wood and I do hereby declare the following is a full and exact description thereof.

The nature of my invention consists in so regulating the heat around and through the retort in which the wood is being distilled as to drive off the oil and spirits, with a portion of the tar, from the rosin and tar which are formed by the distillation, and leave the pitch in the bottom of the retort.

To enable others skilled in the art to make and use my invention, I will proceed to describe the precise process and operation.

Hithertoin the distillation ot'pine wood rosin has been obtained by some ot'the operators and tar by all of them; but pitch has been obtained by none of them directly from the wood, though they could, of course, manufacture pitch from this rosin as tar in the usual way.

I manufacture pitch directly from pine wood in a single distillation, the rosin and tar falling from the wood into the bottom of the retort, and there being converted into pitch by having the oil and spirits, together with the light tar, driven 0E, and leaving the pitch in I the bottom of the retort while the wood is being distilled. This is done by heating the retort or still in which the wood is placed on the bottom or on the sides so nearly to the bottom to such, a degree of heat that the pitch will be lormed of the requisite degree of hardness. by

the time the wood is thoroughlycharred. The degree of heat required to eflect this will depend upon the degree of hardness which it is desired the pitch shall have and the length of time consumed in charringthe wood. Of course, the longer the wood is charting theless will be the degree of heat necessary to form the pitch ot' the desired hardness.

The pitch ma y be examined occasionally and drawn out whenever suificieutly hard.

The heat, if applied directly to the bottom of the re ort, should not be sufi'iciently great to destroy the pitch, and in general should be so regulated with that around the retort as to give the required hardness of pitch at or about the time the charting of the wood is completed. Toward the latter part of the charring a considerable pitch is formed directly in the wood, and'drops therefrom as the heat is continued.

The pitch made by this process is of a very superiorquality, while the quantity ofthe oilor spirits of turpentine and tar, which is driven OH is increased, and the coal is entirely ireed from tar,'aml is found to be extremely dense and lustrous. l

Having thus described my invention, what I claim, and desire to secure by Letters Patent, i-s

The art of making pitch from pine wood byone distillation.

A- H. EMERY.

Witnesses:

W. A. CRAWFORD, (J. F. EMERY. 

